JDN – SEMWO11 - 1

Development of a series of Cubesats

in an educationalcontext

Jens Dalsgaard NielsenJesper Abildgaard LarsenDep of Electronic SystemsStudent Satellite ProgrammeAalborg University – Denmarkwww.studentspace.aau.dk

{jdn,jal}@es.aau.dk

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Agenda for today

• Who are we

• Our space CV

• Space technology, education, Aalborg Problem Based Learning Model

• The process designing and constructing a satellite

• Problem Based Learning principles

• Some additional facts for AAUSAT3

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• 1992-2006 Ørsted (first danish satellite)• 2001-2003 AAU Cubesat – on the first cubesat ever :-) • 2003-2005 ESA SSETI EXPRESS • 2003-2009 AAUSAT-II• 2009-2010 AAUSAT-II operations• 2004-2006 Baumanetz (lost during launch)• 2006-2011+ GENSO global ground station system• 2008-2009 AAUSAT3/BEXUS ballon flight• 2007-2011 AAUSAT3

• 2010-2012 AAUSAT3.5/DLR-AISAT • 2012-2014 AAUSAT4/QB50• 2011-2014 AAUSAT5/AIS

• 1997 Champ ACS study• 1999 Intelligent Autonomous System(IAS) specialization• 1999+ Danish Micro Satellite Programme: Rømer - terminated• 2002 Best Summer School• 2011 Best Summer School• 2005 STEC 2005 ESA student satellite conference• xxxx Five ESA parabolic flights – one on invitation

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Goal

• Why building student satellites ?

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• Why building student satellites ?

• It's expensive (at least the launch)

• Complicate your life at work and at home

• It's difficult

• Launch time can be delayed a lot• AAUSAT-II – 9 month• Vega Maiden flight ?? (we were invited in ... 2007 ???)• AAUSAT3 11 month – still waiting

• And many more “bad” things

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Goal

• Why building student satellites ?

• The students• We think space is interesting • We would like to do space stuff• We would like to become space engineers

• Educational site/the teachers• We think space is interesting :-)• We will educate “the best engineers in the world” ;-)• We will attract even more students to our university• Scientific view point – not to forget ...

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Aalborg University Educational Model

• Problem and Project based Learning – PBL

• Projects last one semester• 4-7 students i one group with own 24/7 office • Staff supervisor following the group• 15 ECTS credits ~= 50% of their time is for the project

• Few hours at semester start, 100% time in the end

• Courses for approx 15 ECTS ~= 50% of the time• Many hours in semester start, 0 in the end

• In that way you can use your new knowledge from the courses in you project

• You work like a “real engineer” developing a ...

• UNESCO chair in Aalborg in “PBL”

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The typical semester result

• Outcome of a project normally is• A report 100-200 pages (normally written in LaTeX :-)• A prototype - ...

• An EPS• A power plant controller• An unmanned helicopter• Bla bla bla• A framework for a satellite internal network (CSP)• You name it • ...

• All projects are public available in the AAU project database system• Restrictions may occur (when dealing with industry)

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The goal - The best engineering students in the world :-)

• More knowledge and skills than other students• Combine theory and praxis• PCB design, mech design,...• Integration !• No sleep before the satellite is in orbit

• International experience and collaboration• Students is travelling – not professors

• More close relationsship and collaboration with scientific staff• Are participating in research

• Recruitment for PhD students• Recruitment for ESA,...,...,...• Recruitment for commercial space companies

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What they dont tell you!

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What they dont tell you! ;-)

• It takes a lot of time to construct and build a satellite

• It takes a lot of time to construct and build a satellite

• It takes a lot of time to construct and build a satellite

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What they dont tell you! ;-)

• There is no such things as free meals

• You may still be engaged AFTER graduation due to prolongation and delay of launch ... and your own interest

BUT DO IT ANYWAY

A ONCE IN A LIFE TIME OPPORTUNITY

MAY (EVEN) HAVE BIG IMPACT ON YOUR FUTURE

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And in addition ...

• You may need skills that are not “available” in your “lectures/education”• PCB layout• Space soldering• Prof development• Integration• Testing • Enviromental knowledge (aka space)• Management :-)• Working like a real engineer !• Time !!!

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Education versus “sat's”

Normal edu Sat's

Theory +++ +++

System Analysis +++ +++

System Design +++ +++

Prototype + +++

Real Impl EM (+) +++

Real Impl FM/QM ++++

Test + ++++

Operations (+) ++...

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So ...

• You must also take responsibility for your own learning ...

• Which is one of our goals: YOU as a brilliant engineer !!!

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Purpose of MANAGEMENT or

letting the Students be in Charge

• Why do we need management ?

• Who “is” be management ?

• Who is going to be “managed” ?

• How shall it be carried out ?

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ROLES and OWNERSHIP

• Is the satellite “owned” by university(staff) ?

• Is the satellite “owned” by the students ?

• Or even an external partner ?

• Who has (C) to your work

Indicating: To whom belongs the child (sat) ?

AAUSAT3 will be released as open source after launch

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The rules

• All students are equal

• Shared responsibility must not exist

• Asking for help is “mandatory”

• Don't make cover ups on mistakes

• We are all going for the final goal

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Why previous slide ? II• Look for phrase “Free Activity”

• Meaning • Voluntary work from you !!!• You can quit when you want to do that

Without you ...

No satellite up in space

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So ...

• The satellite belongs cleary to the students

• And it is their responsibility to make it fly !

• Staff is here to help and guide

• And participate in management

For the record: DISCLAIMER

• All satellites from Aalborg University has been made by the students – not me and not Jesper

• And we do always refer to them as our students satellites and not our own !

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Management and relations

Our approach:

• Open mind • Open conversations• Meet af “same” level• Social atmosphere

AND • Responsibility• Hard working• Take initiatives• ...

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Management model

DISCLAIMER

• Our interpretation – not the students – they may tell another story

• Our management approach is changing all the time due to • We are getting more clever about management• The students change from year to year

• We are doing research about the educational approach• ... together with people from AAUs PBL “society”

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Management priorities

We would like to ...

• see a satellite to be born within time • See students to take control !!!• Have a smoothly running project• Facilitate that the project to be a succes• help when it is needed• ...• “invisible” guidance

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Management priorities

We would like to ...

• see a satellite to be born within time • See students to take control !!!• Facilitate that the project to be a succes• help when it is needed• ...• Act when (personal) unsolvable problems arise

• People not “performing”• Act when technical solutions may be a major risk to the project

• Deployable “something”• External partners• Doubtable subsystems• ...

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Where staff matters

• It may be hard for students to take tough decisions

• AAUSAT-II• 3 month before delivery: deployable solarpanels was taken out !

• AAUSAT3• Reduction of ambition level (complexity) in some systems• GPS and camera payload taken off – risk minimization

• Staff (me) may be the only person that can take/enforce the decision !

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Semester educational approach – integration with edu

A semester is thematic• Analog electronic, digital ..., control systems, robust systems,...,...

Satellite must be “decomposed” to suit these thematics

• EPS (electronic powersupply): analogue and digital electronic• ADCS (attitude control): kinematics, advanced control theory,...• FLIGHTPLANNER: distributed systems, embedded systems,...• ...

Carried out by staff and students together

We do not have a dedicated space master but has it embedded in our regular master programmes.

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Examples from AAUSAT-II and AAUSAT3

• Onboard computer on 4th semester

• AAUSAT-II payload (radiation sensor) on 5-6 semester

• AAUSAT-II structure incl deployable panels on 10th semester

• AAUSAT-II mech design as master project

• AAUSAT3 fault tolerant communication on 10th semester master

• AAUSAT3 ADCS on master 9-10th semester

• AAUSAT3 AIS receiver 7th semester

• AAUSAT3 GPS integration on 7th semester (foreign students)

• ...

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CONCLUSION 1

• Today a very very short crash course about our way of doing sats

• It works (CV)

• Automatic sorting – only tough guys and girls remain in core crew !!!

• Students has already real life experience when the graduate !

• Fun and ambition together make things work

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www.control.aau.dk/~jdn/rast2011-378.pdf

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AAU CUBESAT 2001-2003

• Mission: to demonstrate “we can”

• Payload ADCS

• Student developed HW/SW

• COTS HW (UHF radio)

SPV

COM ACSCAMPCU

AX25

FLP LOG

MAILBOXES

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AAU CUBESAT

• 2 years development time

• Launch ok (June 2003 – first cubesat launch)

• Very weak beacons receivedmost not decodeable

• Respond on telecommands but answers mostly not decodeable

• AX 25 error detection but NO error correction

• CONSIDERED A BIG SUCCES

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AAUSAT-II 2003-2009+

• Next generation Cubesat from AAU

• 100% homemade

• No reuse from AAU CUBESAT

• Scientific payload• gamma ray burst detector

• based on CdZnTe xtal• ARM7 main OBC• 4 PIC 16 sub processors• CANBUS 250 kbit/sec• no OS and uCos• UHF AX-25

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AAUSAT-II

• Launch April 2008• Operations until spring 2010• Still alive :-)

• after more than 3,5 year

• Full duplex contact• Lot of telemetry down• New SW images uploaded

• Tumbling problems• Some reboot problems• Payload problems

• Considered a big success

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SSETI EXPRESS

• ESA Educational Initiative

• VERY VERY FAST construction• 1.5 year

• AAU did provide• adcs• obc• com• camera• gnd and mcc

• Working perfect for 14 hours• EPS did malfunction :-(

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AAUSAT3

• AIS payload• one HW based radio• one SDR based

• Blackfinn 537

• Tech stuff• worst sensitivity -114 dBm

• best sensitivity ?• depends on SW

• Launch 2012

• Similar AIS module invited as main payload on DLRs AISAT

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AAUSAT3